This topic provides the test results of online transaction processing (OLTP) performance of PolarDB for MySQL 8.0.1 Cluster
- CBO: selects the execution plans that have the minimum costs by using a cost model based on statistics or real-time sample data.
- RBO: determines the execution plans of queries based on the preset rules.
The PolarDB for MySQL 8.0.1 optimizer uses CBO as the primary mode, and uses RBO as an alternative mode in specific scenarios. You can run the ANALYZE command to collect the required statistics, or allow the optimizer to automatically collect the statistics. The statistics include the table size, number of records, density vector, hybrid histogram for a single column, number of distinct values (NDV), and null ratio. The cost model parameters of CBO can be configured in system tables to adapt to software and hardware environments. Meanwhile, the execution paths of queries can be locked or the search scope of CBO can be controlled to prevent the system from generating invalid execution plans.
Dedicated instance family
- Primary node and a single read-only node
- Test results of read-only performance of different specificationsNote In the preceding test, the range_selects parameter is set to 0 and queries on all the ranges are disabled. Therefore, the performance may be higher than expected.
- Test results of write-only performance of different specifications
- Test results of read and write performance of different specifications
- Test results of read-only performance of different specifications
- Primary node and multiple read-only nodesTest results of read-only performanceNote
- The preceding figure shows the test results of read-only QPS when the clusters that are connected by using cluster endpoints are tested.
- In the preceding test, the range_selects parameter is not specified. This indicates that queries on all the ranges are enabled by default.
- In the preceding test, the specifications of each node are 4 cores and 16 GB.
General-purpose instance family
Primary node and a single read-only node
- Test results of read-only performance of different specificationsNote In the preceding test, the range_selects parameter is set to 0 and queries on all the ranges are disabled. Therefore, the performance may be higher than expected.
- Test results of write-only performance of different specifications
- Test results of read and write performance of different specifications